Hoist for construction material

ABSTRACT

A hoist for construction sites, for carrying loads suspended from a crane. The hoist is C shaped, suspended at its top arm by a cable of a crane. The bottom arm carries a hook, typically vertically movable, for lifting and moving loads about in the construction site. Owing to its lateral opening, the hoist can deliver loads into the interior space of floors, using minimal crew and relying mainly on the crane for maneuverability.

FIELD OF THE INVENTION

The present invention relates generally to auxiliary equipment used inthe construction industry. More particularly, the invention relates tohoisting of building material in construction sites.

BACKGROUND OF THE INVENTION

Relocation of building material and associated tools constitutes asubstantial effort on behalf of a construction team in a constructionsite. Transferring of building material from unloading locations tosites of consumption, is a mechanized task, often employing cranes andvarious other mechanical instruments. The present invention providesmeans for minimizing costs, reducing manpower, increasing speed andsimplifying the labour involved in relocation within the framework of aconstruction project.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic description of a suspended hoist of the presentInvention;

FIG. 1B is a schematic description of a suspended hoist of the presentinvention showing an insertion of the sliding wheel on a floor;

FIG. 1C is a schematic description of a suspended hoist of the presentinvention being lodged on a subtending floor;

FIG. 2A is a schematic description of a preferred embodiment of asuspended hoist of the present invention showing pulley and cableassembly;

FIG. 2B is a schematic description of a suspended hoist of the presentInvention being lodged on a subtending floor;

FIG. 3 is a schematic description of an embodiment of the invention inwhich the hook pulley is vertically translocatable suspended from asecond pulley and an anchor point.

DESCRIPTION OF THE PRESENT INVENTION

A hoist in accordance with the present invention is a suspended “C”shaped construction or frame having two substantially parallel armsconnected by a cross construction element. The hoist moves both sidewaysand vertically, directed by a crane. A hoist of the invention is aconstruction carrying a hook for material loading, and typically a wheelor a sled for sliding on the floor and a cable system for maneuveringthe hoist and or controlling loading/unloading. Functionally, the hoistof the invention is applicable in construction sites in which floors arelaid sequentially, leaving free access from the flanks. The function isexplained in reference to FIGS. 1A-D. In FIG. 1A a hoist 50 is shownschematically, in a suspended position, hanging on cable 52 which islinked to a crane (not shown). Cable 54 carries a tray 56 with buildingmaterial (not shown). Sliding wheel 58 disposed at the front end of theupper arm of the frame points towards floor 60. This floor and all otherfloors of the building are held by columns such as column 62. In FIG. 1Bthe hoist, suspended still on a crane cable, is pushed in the directionof arrow 68, advancing the hoist over the floor 60. Concomitantly, thehoist 50 is lowered in the direction of arrow 70, by the elongatingcable 52, until sliding wheel 58 meets the upper surface of floor 60. Ascable 52 is elongated still further, the entire hoist 50 rotates aroundsliding wheel 58, bringing the tray 56 further in the direction ofarrows 68 and 70. In FIG. 1C hoist 50 is shown, after maneuvering hasended. Frame 22 of the hoist rests against a support 74. Cable 52 is nolonger required to be tensioned, because the hoist rests firmly againstthe floor 60, through the mediation of support 74. Generally, however,such support may not be required if the frame of the hoist is made torest directly against the supporting floor.

A preferred embodiment of the invention is demonstrated, structure andfunction, with reference to FIGS. 2A-B, which shows a structure of ahoist in accordance with a preferred embodiment of the invention. Hoist80 contains a frame 82, a sliding wheel 84, a set of pulleys 86-89 thatsupport cable 90, a hook 92, cable fastener 94 and a static framesupport 96. In this figure, the hoist is shown suspended in the airtypically carrying a tray of building material (not shown), by hookingon to hook 92. As can be seen, pulley 88 the pivot of which is connectedto frame 82, is adjacent pulley 89 which has a free pivot only connectedto hook 92. This adjacency is brought about by the tension of cable 90which, at the top is anchored directly or indirectly to the crane, andat the bottom to fastener 94. The configuration of pulleys—cableassembly, is changed when the hoist Is made to rest on top of a floor.This is shown schematically in FIG. 2B. Tile 110 represents the floor onwhich the hoist rests. Once the hoist is lodged on floor 110, cable 112can be slackened without affecting the position of the hoist. However,such slackening translates into lowering of hook 114. As can be seen inthe figure, pulleys 116 and 118 are departed since pulley 118 is notconnected to frame 120, but rather to hook 114. Tensioning of liftingcable 112 results in hook 114 being drawn up, providing that the forceapplied is strong enough to lift up the hook and suspended material tray(not shown). Lifting up of the hook may occur until pulley 118 abuts onpulley 116. If the cable is tensioned further, the hoist may be liftedoff the subtending floor providing that the tensioning force canovercome the suspended weight. If the load on the hook is heavier then acertain limit, the tensioning of the lifting cable may cause upliftingof the entire frame. In such cases, anchoring of the lodged frame to thesubtending floor may be required.

In another preferred embodiment of the present invention, an independentwinch is located at the bottom arm of the frame of the hoist, providinga means for lifting/lowering the hook. This is explained with referenceto FIG. 3. In this embodiment, the cable 150 suspended from the crane isfled statically to the hoist. Reel 152 is actuated by a motor (notshown) which winds cable 154 or leases it such that hook 156 moves upand down in the direction of arrow 158, as actuated by the operatorcontrolling the motor. Cable 154 slides in the route as formed by thepulleys 160 and 162. In another constructional variation of the sameembodiment, the lower arm of the hoist is used as a sliding rail trackfor pulleys that carry the load along. A Mechanical relocation facilityalong a horizontal track may be useful if precision placement of gear ormaterial is a required.

1. A hoist for relocating at least building material, wherein said hoistis suspended from a crane, said hoist comprising: a “C” shaped framehaving two arms; a sliding means disposed at the front end of the upperarm of said frame for sliding said frame on a floor; a lifting cable forconnecting to a crane; a hooking means connected to the lower arm ofsaid frame for suspending material tray on said frame.
 2. A hoist forrelocating at least building material as in claim 1, and wherein saidlifting cable is used also to adjust the distance of said hook from saidframe when said frame is lodged on a floor.
 3. A hoist for relocating atleast building material as in claim 1, and wherein said sliding means isa wheel.
 4. A hoist for relocating at least building material as inclaim 1, and wherein said hooking means is at least verticallyrelocatable with respect to said frame.
 5. A hoist for relocating atleast building material as in claim 1, and wherein said hooking means ishorizontally relocatable along the lower arm of said frame.
 6. A methodfor relocating building material by a hoist suspended from a crane,wherein said hoist is “C” shaped having two substantially parallel armsinterconnected by a cross element, and wherein a first of said two armscarries a load, and wherein a second arm substantially parallel to saidfirst arm slides along a floor of a building, providing support for saidhoist.